Digital images often contain objects of interest and can be displayed at various resolutions and at various points in time. In addition, digital images often contain noise or less relevant features in various amounts depending on the device used to collect the data associated with the digital image and the level of resolution. In particular, obtaining a digital image using inferential techniques such as radiographic, echographic, or ultrasonic techniques can be especially susceptible to blurring between the object of interest and noise (or less relevant features) due to, e.g., electromagnetic effects. In some applications, an ultrasound technician captures an image using an image capture device that captures still images or sequences of still image frames (e.g., video). The ultrasound technician can annotate the captured image using an input device to mark, for example, landmarks within the image, distances between points in the image, or other features.
In certain circumstances, useful information can be obtained by comparing an image of a moving object captured at one time t1 with an image of the object captured at a different, e.g., later, time t2. For example, the effectiveness of a treatment regimen can be monitored by comparing an ultrasound image of the transgastric short axis view (TGSAV) of a human heart under observation at time t1 with an ultrasound image of the TGSAV of the same heart at time t2. Typically, comparisons between such ultrasound images are facilitated by displaying an image and objects therein at time t1 alongside a second image at time t2 on a single display monitor (e.g., the images are displayed side-by-side).
One drawback to displaying ultrasound images side-by-side is that differences between the images or objects therein can be obscured due to noise or presence of less relevant features in the images. Additionally, side-by-side comparison does not readily facilitate comparison between objects present in each image when the image capture device or the objects may have moved between time t1 and time t2 or when the objects appear out of scale between the images. Moreover, visually comparing two objects from different images in different fields of view can be time consuming for the ultrasound technician or medical or healthcare personnel (e.g., a doctor) seeking to visually assess the efficacy of a course of treatment.